For older adults doing light weight training, pushing muscles to complete exhaustion doesn't give extra benefits like more strength or muscle growth compared to stopping before exhaustion, since both ways work about the same after 12 weeks.

This claim says that light weight training doesn't really help older adults get bigger muscles, move faster, or get up and go quicker after doing it twice a week for 12 weeks.

Older adults doing light weight lifting twice a week for 12 weeks can get about 20% stronger, even if they don't push themselves to their absolute limit every time.

When lifting lighter weights, you need to push until you can't do any more reps to build as much muscle as lifting heavy weights. But with heavy weights, you can build a lot of muscle without pushing to total exhaustion.

Lifting heavy weights and lifting lighter weights both build muscle about the same amount in healthy adults, as long as you do enough reps until you can't lift anymore.

For beginners lifting weights, pushing muscles to complete exhaustion doesn't build more muscle than stopping just short of exhaustion, as long as the total amount of lifting is the same over 8 weeks.